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1.
J Biotechnol ; 164(2): 276-80, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23274918

RESUMO

Recombinant full-length diguanylate cyclases (DGCs) of Thermotoga maritima with native and mutant allosteric sites were overexpressed in Escherichia coli cells and characterized. It has been shown that target enzymes are produced substantially in the form of active inclusion bodies. Introduction of the mutation in allosteric site resulted in 7-fold increase of the T. maritima DGC activity. Possibility of applying full-length DGC of T. maritima in the form of inclusion bodies for synthesis of c-di-GMP was originally demonstrated.


Assuntos
GMP Cíclico/análogos & derivados , Proteínas de Escherichia coli/metabolismo , Corpos de Inclusão/metabolismo , Fósforo-Oxigênio Liases/metabolismo , Thermotoga maritima/enzimologia , Sítio Alostérico , Biotecnologia , GMP Cíclico/análise , GMP Cíclico/metabolismo , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Mutação , Proteínas Recombinantes/metabolismo , Sais
2.
Med Tr Prom Ekol ; (4): 1-9, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11503227

RESUMO

Chemical weapons elimination on Russian Federation territory positions some problems that should be solved to prevent harm for public health and environment in Russia. The author specified corresponding methodic recommendations.


Assuntos
Substâncias para a Guerra Química/efeitos adversos , Conservação dos Recursos Naturais , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental , Humanos , Federação Russa
3.
Prikl Biokhim Mikrobiol ; 36(1): 8-12, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10752076

RESUMO

The properties of the phosphatase present in the culture liquid of Spicaria violacea were investigated. Based on these results, a method for preparative dephosphorylation of calcium salts of 2'(3')-mononucleotides was proposed. A 96-98% yield was achieved at a substrate concentration of 100 mg/ml. Mild quantitative hydrolysis of RNA to nucleosides can be performed by RNA digestion to mononucleotides with Ca2+ followed by the proposed dephosphorylation procedure.


Assuntos
Monofosfato de Adenosina/metabolismo , Fungos/enzimologia , Monoéster Fosfórico Hidrolases/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/metabolismo , Fosforilação
4.
Nucleosides Nucleotides ; 18(4-5): 687-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10432666

RESUMO

Chemical and enzymatic methods were employed for the synthesis of the title compound, 2'F-Guo 7. High antiviral activity of 2'F-Guo was established in chick embryo cells infected with influenza virus FPV/Rostock/34 (H7N1) and herpes simplex virus (HSV) type I (1C strain).


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Desoxiguanosina/análogos & derivados , Animais , Embrião de Galinha , Desoxiguanosina/síntese química , Desoxiguanosina/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Orthomyxoviridae/efeitos dos fármacos
5.
Prikl Biokhim Mikrobiol ; 31(5): 494-7, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7491361

RESUMO

The influence of temperature and Ca2+ ions at different concentrations on the effectiveness of RNA precipitation from water-salt extract of baker yeast was studied. Our findings allowed us to propose a method for producing highly purified RNA by precipitation with 180 mM Ca2+ ions from hot yeast extracts (95 degrees C) after removal of the protein fraction that could be also precipitated with 20 mM Ca2+ at 90 degrees C. The purity and yields of RNA samples obtained in such a manner was of 98% and 56% relative to theoretical values, respectively.


Assuntos
Cálcio , RNA Fúngico/isolamento & purificação , Saccharomyces cerevisiae/genética , Precipitação Química , Temperatura Alta
6.
Prikl Biokhim Mikrobiol ; 31(3): 308-10, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7638156

RESUMO

The use of barium salts of ribose 1-phosphate and 2-deoxyribose-1-phosphate as the donors of the carbohydrate part of the required nucleosides in the reaction of enzymatic glycosylation of heterocyclic bases was studied. It was shown that application of indicated substrates in the synthesis of modified nucleosides-ribothymidine and bromovinyldeoxyuridine, catalyzed by the nucleoside phosphorylases from Escherichia coli BM-11, leads to the 96-98% yield of required products even at an equimolar ratio of original pentose 1-phosphates and heterocyclic bases in the reaction mixtures.


Assuntos
Compostos de Bário/química , Bromodesoxiuridina/análogos & derivados , Pentosefosfatos/química , Pentosiltransferases/metabolismo , Uridina/análogos & derivados , Bromodesoxiuridina/metabolismo , Catálise , Escherichia coli/enzimologia , Fermentação , Glicosilação , Indicadores e Reagentes , Uridina/biossíntese
7.
Appl Microbiol Biotechnol ; 32(6): 658-61, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1367439

RESUMO

Synthesis of 9-(beta-D-arabinofuranosyl)guanine (ara-G) from 1-(beta-D-arabinofuranosyl)cytosine (ara-C) and guanine, guanosine or 2'-deoxyguanosine (dG) by glutaraldehyde-treated Escherichia coli BM-11 cells is described. It is shown that the concentration of phosphate ions, molar ratio of substrates and pH of the reaction medium are factors affecting product yield. Under optimum conditions ara-G was produced in the reaction mixture in a yield of 63%-65% based on dG as the best source of guanine base. The yield of isolated ara-G was 48%-53%.


Assuntos
Arabinonucleosídeos/biossíntese , Escherichia coli/metabolismo , Arabinonucleosídeos/isolamento & purificação , Proteínas de Bactérias/metabolismo , Citarabina/metabolismo , Citosina Desaminase , Glutaral , Guanina/metabolismo , Nucleotídeos de Guanina/metabolismo , Nucleosídeo Desaminases/metabolismo , Purina-Núcleosídeo Fosforilase/metabolismo , Uridina Fosforilase/metabolismo
9.
Antibiot Med Biotekhnol ; 31(3): 174-8, 1986 Mar.
Artigo em Russo | MEDLINE | ID: mdl-3521466

RESUMO

The conditions of synthesis of 9-beta-D-arabinofuranosyladenine, an antiviral nucleoside by intact cells of Escherichia coli capable of adenine transarabinosylation were studied. The cells were grown in meat-peptone broth supplemented with yeast extract. Cytosine arabinoside served as a donor of the arabinose residues. The pH value, temperature of the reaction medium and concentration of phosphate ions in it were shown to be significant factors defining the cell activity. Under optimal reaction conditions: 0.03 M potassium phosphate buffer, pH 6.75; 0.03 M cytosine arabinoside; 0.01 M adenine; 5 per cent of the cells; incubation time 12 hours; incubation temperature 60 degrees C the efficiency of 9-beta-D-arabinofuranosyladenine synthesis reached 90-95 mol % with respect to the initial adenine level.


Assuntos
Antivirais/metabolismo , Escherichia coli/enzimologia , Vidarabina/biossíntese , Adenina/metabolismo , Tampões (Química) , Meios de Cultura/metabolismo , Citarabina/metabolismo , Relação Dose-Resposta a Droga , Concentração de Íons de Hidrogênio , Temperatura Ambiente
10.
Antibiot Med Biotekhnol ; 30(8): 588-91, 1985 Aug.
Artigo em Russo | MEDLINE | ID: mdl-2998272

RESUMO

Strain 47/3 was isolated from the natural sources of Erwinia herbicola. The cells of this strain contain nucleoside phosphate transferase responsible for specific phosphorylation of the adenosine 5'-hydroxyl group. With the use of the strain intact cells, conditions for preparation of AMP were determined. The cells were grown in the meat-peptone broth supplemented with yeast extract. p-Nitrophenylphosphate was used as a donor of phosphate groups. It was shown that the concentration of the reaction substrates, their ratio and PH of the reaction mixture were factors defining the cell activity. Under the optimal conditions (0.2 M acetate buffer, pH 4.5; concentrations of p-nitrophenylphosphate and adenosine 96 and 12 mg/ml respectively; concentration of the cells 1 per cent) the cells phosphorylated adenosine with a yield of 74 mol %. This indicates that the method may be used for production of AMP in preparative amounts.


Assuntos
Monofosfato de Adenosina/biossíntese , Adenosina/metabolismo , Erwinia/enzimologia , Meios de Cultura/metabolismo , Relação Dose-Resposta a Droga , Concentração de Íons de Hidrogênio , Nitrofenóis/metabolismo , Compostos Organofosforados/metabolismo , Fosforilação , Fosfotransferases/metabolismo , Temperatura Ambiente
11.
Biokhimiia ; 43(7): 1184-9, 1978 Jul.
Artigo em Russo | MEDLINE | ID: mdl-698306

RESUMO

The binding of the receptor-glucocorticoid complexes from rat liver cells to DNA has been studied in an aqueous dextran-polyethylene glycol biphasic system. It has been shown that the capacity of DNA for binding hormone-receptor complexes is very large, and that no saturation is observed at physiological concentrations of the glucocorticoid receptor. The linear binding curve is indicative of low affinity of the DNA acceptor sites for the complexes. Cell cytosol contains substances which inhibit the binding of the receptor-dexamethasone complexes to homologous DNA.


Assuntos
DNA/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Esteroides/metabolismo , Animais , Citosol/metabolismo , Dextranos , Fígado/metabolismo , Polietilenoglicóis , Ratos
12.
Biokhimiia ; 42(6): 1090-6, 1977 Jun.
Artigo em Russo | MEDLINE | ID: mdl-889973

RESUMO

An early described hypothetical scheme is confirmed on transformation of non-covalent polynucleotide-protein interactions into covalent under the treatment of CD phage with O-methylhydroxylamine. 4 proteins are revealed, which have been covalently bound to cytosine of DNA during modification process. Fractionation of these proteins in polyacrylamide gel in the presence of sodium dodecylsulphate has revealed that three of them migrate as head structural proteins, and the rest--as internal phage CD protein. Possible mechanisms of the effect of phage protein on the reaction of DNA cytosine residues with O-methylhydroxylamine are discussed.


Assuntos
Bacteriófagos/metabolismo , Hidroxilaminas/farmacologia , Proteínas Virais/metabolismo , Citosina/metabolismo , DNA Viral/metabolismo , Ligação Proteica , Proteínas Virais/isolamento & purificação
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